Question

we use two expression :(i) H=I2RT (ii) H=V2/R*t for calculating the energy consumed by a device . out of these two expression the first expression indicates that the energy consumed is directly proportional to R whereas the second expression indicates that the energy consumed is inversely proportional to R . how can we explain the seemingly different dependence of H on R in these expression

Answer 1

in this first expression there v as constant. in second expression there I is constant .so they expressed directly and inversely.

Answer 2

The expression H=I^2R holds when current I remain constant . The expression H=V^2/R holds when potential difference V remains constant . Both the expression for electric power are correct